The Mens Cold Terrain Texapore Mid Boot from Jack Wolfskin is lined with fleece for an extra portion of insulation. It keeps your feet warm in temperatures down to -20°. The weatherproof membrane makes it fully waterproof. It is made entirely of synthetic materials, so it requires less care and maintenance than a leather boot. The Wolf Snow sole is made of a special rubber compound and has an advanced tread design for a secure grip on winter terrain.